The present invention relates to a fixing structure for parts of optical element, particularly it relates to a fixing structure for parts of optical element which is utilized in copying machine, facsimile machine, image scanner and so on, in which the solid state image forming device is used to input optical image.
Generally an image data input apparatus in which optical image is input as optical signal using solid state image forming device such as CCD, inputs image of object 901 focused on solid state image forming device 903 through image focusing lens 902 as shown in FIG. 14. In the solid state image forming device 903, one line of solid state image forming device is utilized in which plurality of micro photoelectric transforming devices (hereinafter it is referred to as merely xe2x80x9cpixelxe2x80x9d, which usually has a small dimension of some micrometers square) are arranged in straight line.
Recently, in order to input colored images there is a case in that the solid state image forming device 906 in which pixel R(906a), G(906b) and B(906c) having a peak of spectroscopic sensitivity in Red (hereinafter referred to as merely xe2x80x9cRxe2x80x9d), Green (hereinafter referred to as merely xe2x80x9cGxe2x80x9d) and Blue (hereinafter referred to as merely xe2x80x9cBxe2x80x9d) respectively, are arranged in three lines respectively, is used as shown in FIG. 15.
Usually accurate positioning adjustment of such solid state image forming device 906 is requested in high precision for every five dimension respectively, and what is seemed to be indispensable to attain the request is a technology by which discrepancy of positioning of solid state image forming device 906 is not happened when the solid state image forming device 906 is fixed onto a flame after the position of solid state image forming device 906 is adjusted as above stated.
The reason such technology is requested is because even the positioning has been adjusted with high precision, when discrepancy is happened at fixing, positioning adjustment must be needed again or separable parts must be scraped when the fixing method includes separable but not adjustable parts.
Up to now the fixing is mainly achieved by screws, however, when such kind of fixing method is utilized, a problem is happened that an amount of discrepancy becomes large such an ranged between some tens micro meters and some hundreds micro meters
To solve this kind of inconvenience it may take into consideration that complicated mechanism and parts comprising arrowheads, balls and springs instead of screw are utilized, however, the cost increases much more because the components are expensive.
Accordingly, at present a fixing by adhesive material is mainly tried which is thought that amount of discrepancy is much less than that by screws and that problem regarding to number of parts is much less. There are two methods in the fixing by adhesive material when it is classified roughly, one is a method for the case that objects to be fixed together in contacting each other, and another is a method for the case that objects to be fixed together is not contacting with space.
Herein the former is called as contacting adhering method and the latter is called as causing adhering method.
In the caulking adhering method, there is a space which is larger than that for space adjusting, and the adhesive material is introduced and filled the apace in order to fix. As a prior art technology of this kind of caulking adhering method, it is disclosed, for example, in Japanese Patent Laid Open No. Hei 7-297998. The technology settles the space between the objects to be adhered so that the objects to be adhered would not contact each other even when they have problem of accuracy in shape and size and the adhesive material is filled between the space to fix.
Also as an attaching method onto a head holding member through an ultraviolet setting adhesive material, there is a method as shown in FIG. 16.
In the method shown in FIG. 16, adhesive material 912 is painted on one surface of a work piece 911 and the work piece 911 is adjusted for its positional relation to a work piece holding member 913 as shown in FIG. 16(A). When the work piece 911 is fixed onto the work piece holding member 913 through the adhesive material 912, by irradiating ultraviolet to the adhesive material 912 through a light guide L from a space between the work piece 911 and the work piece holding member 913, the adhesive material 912 is hardened to fix the work piece 911 onto the work piece holding member 913 as shown in FIG. 16(B). Herein, when either one of the work piece 911 or the work piece holding member 913 is made of a ultraviolet transparent material, the ultraviolet may be passed through the transparent material to irradiate the adhesive material 912.
However, in the prior art technique such as described above, because the amount of space is settled so that the objects to be fixed would not contact each other and the adhesive material is filled between the space to fix, problems as listed below have taken place.
Hereinafter, this caulking adhering method will be explained with reference to a drawing of one example as shown in FIG. 17, and the problems of it will be concretely explained.
In FIG. 17, the reference numeral 914 designates a work piece to be adhered, 915 designates a work piece holding member and 916 designates the adhesive material, the work piece 914 will be fixed onto the work piece holding member 915 in this example.
To adhere and fix the work piece 914 on the work piece holding member 915 without contacting each other, a space B is required in order to keep a space to be filled by the adhesive material 916 so that the adhering surface 914a of work piece 914 and the adhering surface 915a of work piece holding member 915 would not contact each other even when an amount of dispersion in positional discrepancy is A (spacing for positioning adjustment of work piece 914) at the adhering surface 914a of work piece 914, and an amount of dispersion in discrepancy C at the adhering surface 915a of work piece holding member 916, occur. In consequence of this the film thickness of adhesive material 916 varies from B at the minimum and to A+B+C at the maximum, then it becomes dispersing in a range A+C.
Further, it may also become dispersing in a range I+J because of influence of a surface accuracy in the adhering surface 914a of work piece 914 and the adhering surface 915a of work piece holding member 915.
Generally, as the adhesive material shrinks when it is hardened, it becomes important that the film thickness of adhesive material must be reduced as little as possible in order not for the objects to be fixed to have the positional discrepancy after the adhesive material has been hardened. On the contrary, as the film thickness of adhesive material can not be made less than B in the above described caulking adhering methods there was a case in that an improvement in the amount of positional discrepancy after fixing, could not be realized because changing of film thickness as a counter measure could not be applied even the positional discrepancy happened with amount much larger than the tolerable amount when the film thickness of adhesive material is B.
And because the dispersion of the film thickness happens within a range of A+C, the amount of shrinkage at the adhesive material after fixing, changes together in accordance with the dispersions In the consequence of this, the position of work piece 914 also disperses and there was a case in that the required accuracy could not be maintained. Commonly the volume shrinkage rate of ultraviolet setting adhesive material is in a range from 5 to 10 percent. Presuming a case that the volume shrinkage rate is 7%, it shrink about 2% in each respective three directions when the hardening shape of adhesive material is cubic.
In consequence of this, when the difference in a level of about 0.5 mm occurs in the film thickness of adhesive material, it causes that about 10 xcexcm of differences in the shrinkage after hardened, occur in respective directions. In a case when the objects to be fixed are made by injection molding of resin, there can be a case in that above described dispersion of film thickness A+C becomes more than 0.5 xcexcm, there is enough possibility that the positional discrepancy becomes a fatal problem.
As above described, because there may happen a case that the required accuracy of fixing position for ink jet work piece is not maintained by the prior caulking adhering method, a yield in production line is made to be decreased or there must be a disposal for scrapping the objects fixed, which is not good in accuracy of fixing, then they makes problem happened that costs for production are increased.
To solve this kind of problems, there is a technique disclosed in Japanese Patent Laid Open No. Hei 10-309801.
This fixing structure is arranged in that lying an intermediate holding member between a work piece and a work piece holding member and fixing the intermediate holding member onto the work piece by adhesive material and at the same time fixing the intermediate holding member onto the work piece holding member through the adhesive material. Because of this lying structure of the intermediate holding member between the work piece and the work piece holding member, by means of only controlling to make minimum for necessity and constant the film thickness of the adhesive materials those are used for a space between the adhering surfaces of the work piece and the intermediate holding member, and used for a space between the adhering surfaces of the work piece holding member and the intermediate holding member, this technology can achieve to attach the work piece onto the work piece holding member with high accuracy, and to keep high yield of production and at the same time to prevent occurrence of decrease in fixing force of the work piece after production without controlling the positional accuracy of adhering point of the work piece and the work holding member.
However, the above described technology has still problem to be improved when it is applied to a case that a solid state image data input unit is the work piece and a solid state image data input unit holding member is the work piece holding device and an intermediate holding member is lying through adhesive material between the solid state image data input unit and the work piece holding member, because it has not a concrete structure in order to enable the high accuracy attachment of the solid state image data input unit after the easy positional adjustment in five axes of the solid state image data input unit, in the positional adjustment of the solid state image data input unit before fixing by the adhesive material, a line image focused by an image focusing lens is positioned on the solid state image forming device and an optical characteristics of them are measured with a required predetermined accuracy, and to prevent an occurrence of decrease in fixing force of the solid state image data input unit after production.
In consequence of this, the present invention has an object to provide a fixing structure for the parts of optical element by which attaching of the parts of optical element is enabled to easily achieve a positional adjustment in the axis of the parts of optical element with high accuracy after positional adjustment has done in the axes before fixing of the parts of optical element by adhesive material, and an image data input unit and an image data input apparatus which are made with the fixing structure.
To achieve the above stated object, according to the first aspect of this invention, a fixing structure for parts of optical element comprising: parts of optical element having an edge surface which is a side surface surrounding a light beam passing surface; an intermediate holding member having a first attaching surface which is facing to said side surface and having a second attaching surface which is arranged in a different angle from said first attaching surface; and a base member having an attaching surface which is facing to said second attaching surface; characterized in that: the base member and said parts of optical element which has been adjusted the positional relation to the base member are adhered and fixed through said intermediate holding member, is provided.
Also to achieve the above stated object, according to the second aspect of this invention, a fixing structure for parts of optical element according to above first aspect characterized in that a photoelectric transforming member is fixed on said base member in a predetermined positional relation with said parts of optical element, is provided.
Further to achieve the above stated object, according to the third aspect of this invention, a fixing structure for parts of optical element according to the first aspect characterized in that the adhesive material used for said adhesion and fixing is light setting adhesive material, and said intermediate holding member is transparent for at least light which hardens said light setting adhesive material, is provided.
Still further to achieve the above stated object, according to the fourth aspect of this invention, a fixing structure for parts of optical element according to the first aspect, characterized in that said first attaching surface and said second attaching surface of said intermediate holding member are made to be perpendicular, is provided.
Yet further to achieve the above stated object, according to the fifth aspect of this invention, a fixing structure for parts of optical element according to the fourth aspect, characterized in that said intermediate holding member bas rib.
Yet further to achieve the above stated object, according to the sixth aspect of this invention, a fixing structure for parts of optical element according to the first or fourth aspect, characterized in that said parts of optical element has a flat portion which faces to the first attaching surface of said intermediate holding member on a side surface of said parts of optical element, is provided.
Yet further to achieve the above stated object, according to the seventh aspect of this invention, a fixing structure for parts of optical element according to the sixth aspect, characterized in that said flat portion is parallel to an optical axis of said parts of optical element, is provided.
Yet further to achieve the above stated object, according to the eighth aspect of this invention, a fixing structure for parts of optical element according to the sixth aspect, characterized in that said flat portion is formed by grinding of side surface of said parts of optical element, is provided.
Yet further to achieve the above stated object, according to the ninth aspect of this invention, a fixing structure for parts of optical element according to the first aspect, characterized in that the fixing structure further comprising a spacing member having a side contacting surface which is aligned with side surface of said parts of optical element, and having aligning surface which is aligned with said first attaching surface of the intermediate holding member, characterized in that said side contacting surface of the spacing member faces to the side surface of said parts of optical element, and and aligning surface of said spacing member faces to the first contacting surface of said parts of optical element, is provided.
Yet further to achieve the above stated object, according to the tenth aspect of this invention, a fixing structure for parts of optical element according to the sixth aspect, characterized in that a photoelectric transforming member is fixed on said base member in a predetermined positional relation with said parts of optical element, the first attaching surfaces are arranged in both sides of a best effective region of said parts of optical element for said transforming member is provided.
Yet further to achieve the above stated object, according to the eleventh aspect of this invention, an image data input unit in which solid state image forming device is disposed at a position where an image is focused by an image focusing lens, comprising: lens having an edge surface which is a side surface surrounding a light beam passing surface; an intermediate holding member having a first attaching surface which is facing to said side surface and having a second attaching surface which is arranged in a different angle from said first attaching surface; and a base member having an attaching surface which is facing to said second attaching surface; characterized in that: the base member and the lens which has been adjusted the positional relation to the base member are adhered and fixed through said intermediate holding member, is provided.
Yet further to achieve the above stated object, according to the twelfth aspect of this invention, an image data input unit according to the eleventh aspect, characterized in that said unit further comprising a cover between said image focusing lens and said solid state image forming device, is provided.
Yet further to achieve the above stated object, according to the thirteenth aspect of this invention, an image data input unit according to the eleventh aspect, characterized in that said image focusing lens is composed of plurality of lenses, is provided.
Yet further to achieve the above stated object, according to the fourteenth aspect of this invention, an image data input apparatus utilizing said image data input unit according to any one of the eleventh to thirteenth aspect, is provided.
Hereinafter an embodiment of the present invention will be described with reference to the drawings.